A common procedure for handling pain associated with intervertebral discs that have become degenerated due to various factors such as trauma or aging is the use of intervertebral fusion devices for fusing one or more adjacent vertebral bodies. Generally, to fuse the adjacent vertebral bodies, the intervertebral disc may first be partially or fully removed. Typically, an intervertebral fusion device may then be inserted between neighboring vertebrae to maintain normal disc spacing and restore spinal stability, thereby facilitating an intervertebral fusion.
There are a number of known conventional fusion devices and methodologies in the art for accomplishing the intervertebral fusion. These include screw and rod arrangements, solid bone implants, and fusion devices which include a cage or other implant mechanism which, typically, is packed with bone and/or bone growth inducing substances. These devices are implanted between adjacent vertebral bodies in order to fuse the vertebral bodies together, alleviating the associated pain.
However, there are drawbacks associated with the known conventional fusion devices and methodologies. For example, two important factors in intervertebral fusion may be the anterior (lordotic) angle adjustment and posterior height adjustment. The lordotic angle may be important in restoring sagittal balance while the posterior height may aid in restoring disc height and indirect decompression of the neural foramen. While convention fusion devices may allow for in-situ expansion, they do not allow for the lordotic angle and posterior height to be adjusted in-situ independently of one another.